In order to solve the problems of poor mining safety and high loss and depletion rate of the steeply inclined and soft broken veins in Shanggong Gold Mine, the F1-Ⅲ vein were subjected to on-site industrial experimental research using the quasi-medium-deep hole segmented-open pit method. The results show three aspects. Firstly, all the mining works are arranged in stable rock mass outside the vein, and the safety of the construction process can be ensured by drilling medium-deep holes into the ore body from the roadway outside the vein to control and recover the ore body. Secondly, the non-cutting engineering blasting groove technology, which takes the mine approach as the initial free surface of blasting and the 3-4 rows of holes are simultaneously blasted from bottom to top to form a full section, can significantly reduce safety hazards, reduce mining costs and simplify construction technology. Lastly, the dividing line between the surrounding rock and the vein is accurately determined during the drilling process, the hole is protected by plastic sleeves and the mining is carried out by fine blasting technology. When the stope process parameters are determined as the minimum resistance line of 1.5 m, the row distance of 1.5 m, the hole bottom distance of 2.0 m, and the single explosive consumption of 0.22 kg/t, the blasting effect is the best. The loss rate is reduced to 10.1%, the dilution rate is reduced to 12.4%, the production capacity of the mining site is increased by 54.6 t/d compared to the shallow hole retention method, and the direct mining cost is reduced by 11.06 yuan/t.